摘要:
Disclosed is a system for performing an operation, such as a read or write operation, on a data block in a shared disk system. A first adaptor receives a request to perform an operation on a data block maintained in a data storage location. The first adaptor then determines whether the first adaptor controls access to the data block. The first adaptor performs the requested operation on the data block after determining that the first adaptor controls access to the data block. If the first adaptor does not control access to the data block, then the first adaptor transmits a first message to a second adaptor that controls access to the data block and requests control of access to the data block. After receiving the first message, the second adaptor transfers control of access to the data block to the first adaptor. The second adaptor then transmits a second message to the first adaptor that the first adaptor controls access to the data block. After receiving the second message, the first adaptor performs the requested operation on the data block.
摘要:
Disclosed is a system for updating and destaging data in a storage system. To overcome the limitations in the prior art described above, preferred embodiments of the present invention disclose a system for updating a data block in a storage device. A first processing unit receives an update to a data block in a storage device. The first processing unit sends a first message including the update and information indicating data blocks that were recently updated to a second processing unit. The second processing unit stores the update in a second storage area and sends a second message to the first processing unit after receiving the first message. The first processing unit stores the update in a first storage area and transfers the update from the first storage area to the data block in the storage device. The first processing unit transfers the update from the first storage area to the data block in the storage device. Data may be destaged from the first storage area by sending two messages before destage begins and two messages after destaging is completed so the second processing unit is aware of the state of the destaging operations.
摘要:
Disclosed is a system for altering the structure of parity groups, e.g., altering the RAID level or number of storage devices included in the RAID array. A parity group consists of a set of data blocks and parity data for the data blocks. The data and parity data are stored in at least two storage devices. The first processing unit alters the parity structure of an Nth set of parity groups, wherein N is an integer value greater than or equal to zero. A set of parity groups includes at least one parity group. The second processing unit determines an Nth range of parity groups including the Nth set of parity groups. After detecting the failure of the first processing unit while altering the parity structure of the parity groups in the Nth set, the second processing unit processes the parity groups in the determined Nth range to determine a parity group whose parity structure was being altered when the first processing unit failed.
摘要:
Provided is a method for managing a network providing Input/Output (I/O) paths between a plurality of host systems and storage volumes in storage systems. An application service connection definition is provided for each connection from a host to a storage volume. At least one service level guarantee definition is provided indicating performance criteria to satisfy service requirements included in at least one service level agreement with at least one customer for network resources. Each service level guarantee definition is associated with at least one application service connection definition. Monitoring is performed as to whether Input/Output (I/O) requests transmitted through the multiple I/O paths satisfy performance criteria indicated in the service level guarantee definition associated with the I/O paths.
摘要:
To satisfy host requests, two competing processors self-manage access to a shared resource. Each processor maintains a lock table listing that processor's access state regarding the shared resource. Each processor repeatedly sends the other processor a state announcement message representing the processor's state. These include birth cry, heartbeat, or death knell messages. Whenever certain join-entry conditions apply to a processor, the processor performs a JOIN operation to evaluate and attempt to synchronize its lock table with the other processor's lock table. If data is needed from the other processor's lock table, the processor changes its state announcement message to birth cry. If the processor successfully synchronizes its lock table with the other processor, the JOIN operation dictates DUAL mode for that processor. If the synchronization attempt fails, SOLO results. When JOIN completes, the processor operates in its chosen mode. In DUAL, the processor's state announcement message is heartbeat, signifying healthy operation. In DUAL, the processors cooperatively establish temporary single-processor locks on the shared resource to satisfy host requests. In SOLO, a processor sets its state announcement message to death knell, advising the other processor not to access the shared resource. Also in SOLO, the processor attempts to "acquire" the shared resource by storing a predetermined identifier thereon. In SOLO, a processor refrains from accessing the shared resource unless it has acquired it.
摘要:
Multiple competing processors cooperatively manage access to a shared resource. Each processor separately stores a lock table, listing shared resource subparts, such as memory addresses of a data storage device, for example. The lock tables are stored in nonvolatile storage. In each lock table, each subpart is associated with a “state,” such as; LOCAL or REMOTE. In response to access requests from the hosts, the processors exchange various messages to cooperatively elect a single processor to have exclusive access to the subparts involved in the access requests. After one processor is elected, the lock-holding processor configures its lock table to show the identified subpart in the LOCAL state, and all non-lock-holding processors configure their lock tables to show the identified subpart in the REMOTE state. Thus, rather than replicating one lock table for all processors, the processors separately maintain lock tables that are coordinated with each other. Importantly, each processor honors its lock table by refraining from accessing a subpart of the shared resource unless the processor's lock table indicates a LOCAL state for that subpart. In one embodiment, optimized for the two processor environment, the messages exchanged by the processors include lock request, lock release, and lock grant messages.
摘要:
A system and method for updating data. A first processing unit, such as an adaptor, receives a data update to a data block in a first storage device, such as a hard disk drive. Parity data for the data block is maintained in a second storage device, e.g., another hard disk drive. A parity group is comprised of the data block and corresponding parity data. The first processing unit determines whether the first processing unit controls access to the parity group, i.e., the state of lock ownership. The first processing unit transmits the data update to a second processing unit after determining that the first processing unit does not control access to the parity group. The second processing unit, another adaptor, performs an update after receiving the data update from the first processing unit. The first processing unit performs an update after determining that the first processing unit controls access to the parity group.
摘要:
An apparatus, system, and method are disclosed for reporting on enterprise data processing system configurations. A collection module records a plurality of entity configurations for a DPS in a history database. In one embodiment, a selection module selects a subset of entities of the DPS. A report module generates a historical report of the plurality of entity configurations. In addition, the report module may generate the historical report for the selected subset of the entities.
摘要:
An apparatus, system, and method are disclosed for reporting on enterprise data processing system configurations. A collection module records a plurality of entity configurations for a DPS in a history database. In one embodiment, a selection module selects a subset of entities of the DPS. A report module generates a historical report of the plurality of entity configurations. In addition, the report module may generate the historical report for the selected subset of the entities.
摘要:
A method and system for optimizing the performance of a storage system by classifying each client request for resources based on operational limits of the resources and controlling when to submit the request for processing based on service class. The operational limits are determined from performance characteristics of the system resources and from the level of performance guaranteed to each client. By regulating the clients' usage of resources using the resource operational limits, total system performance requirements and guarantees can be achieved.